The advantages of hard disk drives within computing systems are generally recognized in the main to be significant data storage capacity and rapid random access to the data being stored access which is much faster than slower storage devices, such as floppy disks which typically provide lesser data storage capacity and longer data access times. One drawback of hard disk drives is that the disks are typically fixed within the housing of the disk drive and may not be conveniently removed, either for safekeeping, or for use within another computing system at another location. This drawback is further amplified by the current large sizes of operating systems and applications software (as well as relevant data bases) needed to establish a computing environment. If the computing environment is desired to be transportable from one hardware environment to another similar hardware environment, a high storage capacity, low access time, high performance data storage module is required.
One proposed solution has been a hard disk cartridge, exemplified by the Syquest Technology SQ312RD removable disk cartridge drive. One drawback of the hard disk cartridge is the difficulty in maintaining a very clean environment within the cartridge needed to prevent damage between the data storage disk and a closely flying data transducer head. Another difficulty has been associated with the need to load and unload the data transducer head slider from proximity with the data storage surface without contacting or otherwise causing abrasion or damage to the delicate data storage media formed on the disk surface. Another disk cartridge technology is the so-called "Bernoulli Box" product line, made by lomega Corporation.
Another prior solution has been to include a hard disk drive within a shock-mounting module which may be plugged into and removed from a base unit or receptacle. One example of this prior approach is found in the Dalziel et al. U.S. Pat. No. 4,833,554 which discloses a mechanized receptacle for automatically inserting and removing the hard drive module from the receptacle. One drawback of the Dalziel et al. approach was that the disk drive module was relatively large, and did not fit within a standard space allotted to a disk drive within a computing system, such as a so-called "half-height" 5.25" drive bay within a personal computer.
This drawback was solved by the commonly assigned Blackborow et al. U.S. Pat. No. 5,041,924 entitled: "Removable and Transportable Hard Disk Subsystem", the disclosure of which is incorporated herein by reference. This later invention provided a micro-Winchester (3.5 inch diameter) head and disk module for use within a fully automated module insertion and removal base unit. The base unit occupied no more than the standard 5.25", half height form factor drive bay provided in a typical personal computer for a floppy disk or a hard disk. One drawback of the system described in the referenced and commonly assigned Blackborow et al. U.S. patent was that the interface was limited to a particular host computer architecture, such as the IBM PC or AT architecture. Aesthetic, non-functional details of the drive module are shown in commonly assigned U.S. Pat. No. Des. 311,737 issued Oct. 30, 1990.
A manual drive module/receptacle which fits within a 5.25" half height drive bay in a computer is described in U.S. Pat. No. 4,941,841. This patent describes a concept which appears to be very similar to one advanced in an earlier French patent disclosure document No. 2,594,997, published on Aug. 28, 1987.
More universal interfaces have since become standard for small computing systems. One such interface is the Small Computer System Interface or "SCSI". This interface is a bus-level or "intelligent" interface which is supported on an industry wide basis, and is specified e.g. by ANSI X3.131-1986, Small Computer System Interface Specification Common Command Set, Rev. 4B. One advantage of the SCSI intelligent interface is that it may be used on one side with a virtually unlimited variety of host computing systems, not just one particular system; and, it may be used on the other side with a very wide variety of disk drives having differing data storage capacities, etc.